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Re: Help for a request - SELECT / LEFT JOIN & GROUPS
Posted by: Peter Brawley
Date: October 20, 2016 11:38AM

Looks like an entity-attribute-value (EAV) schema. Queries on EAV databases are nightmares to write, and with more than a few rows they perform like pigs. The leading recommendation would be: lose the EAV model, instead design a standard relational schema.

If you insist on staying with EAV, you'll need quickly to get skilled at what are called pivot table queries. For an intro to this topic see "Pivot table basics: rows to columns" at https://www.artfulsoftware.com/infotree/queries.php.

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Re: Help for a request - SELECT / LEFT JOIN & GROUPS
October 20, 2016 11:38AM


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